A. If the malfunctioning traffic signal is causing a traffic hazard please call 911. It not it can be reported directly to the Department of Transportation Services. You can call them during business hours Monday through Friday from 7:30 a.m. to 4:30 p.m. at (808) 768-8387 or 768-5323. If you reached them afterhours, you can call HPD to report malfunctions.